1 files changed, 113 insertions, 0 deletions
diff --git a/src/net/dnsmsg_test.go b/src/net/dnsmsg_test.go
new file mode 100644
index 000000000..c39dbdb04
--- /dev/null
+++ b/src/net/dnsmsg_test.go
@@ -0,0 +1,113 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package net
+
+import (
+	"encoding/hex"
+	"reflect"
+	"testing"
+)
+
+func TestDNSParseSRVReply(t *testing.T) {
+	data, err := hex.DecodeString(dnsSRVReply)
+	if err != nil {
+		t.Fatal(err)
+	}
+	msg := new(dnsMsg)
+	ok := msg.Unpack(data)
+	if !ok {
+		t.Fatalf("unpacking packet failed")
+	}
+	msg.String() // exercise this code path
+	if g, e := len(msg.answer), 5; g != e {
+		t.Errorf("len(msg.answer) = %d; want %d", g, e)
+	}
+	for idx, rr := range msg.answer {
+		if g, e := rr.Header().Rrtype, uint16(dnsTypeSRV); g != e {
+			t.Errorf("rr[%d].Header().Rrtype = %d; want %d", idx, g, e)
+		}
+		if _, ok := rr.(*dnsRR_SRV); !ok {
+			t.Errorf("answer[%d] = %T; want *dnsRR_SRV", idx, rr)
+		}
+	}
+	_, addrs, err := answer("_xmpp-server._tcp.google.com.", "foo:53", msg, uint16(dnsTypeSRV))
+	if err != nil {
+		t.Fatalf("answer: %v", err)
+	}
+	if g, e := len(addrs), 5; g != e {
+		t.Errorf("len(addrs) = %d; want %d", g, e)
+		t.Logf("addrs = %#v", addrs)
+	}
+	// repack and unpack.
+	data2, ok := msg.Pack()
+	msg2 := new(dnsMsg)
+	msg2.Unpack(data2)
+	switch {
+	case !ok:
+		t.Errorf("failed to repack message")
+	case !reflect.DeepEqual(msg, msg2):
+		t.Errorf("repacked message differs from original")
+	}
+}
+
+func TestDNSParseCorruptSRVReply(t *testing.T) {
+	data, err := hex.DecodeString(dnsSRVCorruptReply)
+	if err != nil {
+		t.Fatal(err)
+	}
+	msg := new(dnsMsg)
+	ok := msg.Unpack(data)
+	if !ok {
+		t.Fatalf("unpacking packet failed")
+	}
+	msg.String() // exercise this code path
+	if g, e := len(msg.answer), 5; g != e {
+		t.Errorf("len(msg.answer) = %d; want %d", g, e)
+	}
+	for idx, rr := range msg.answer {
+		if g, e := rr.Header().Rrtype, uint16(dnsTypeSRV); g != e {
+			t.Errorf("rr[%d].Header().Rrtype = %d; want %d", idx, g, e)
+		}
+		if idx == 4 {
+			if _, ok := rr.(*dnsRR_Header); !ok {
+				t.Errorf("answer[%d] = %T; want *dnsRR_Header", idx, rr)
+			}
+		} else {
+			if _, ok := rr.(*dnsRR_SRV); !ok {
+				t.Errorf("answer[%d] = %T; want *dnsRR_SRV", idx, rr)
+			}
+		}
+	}
+	_, addrs, err := answer("_xmpp-server._tcp.google.com.", "foo:53", msg, uint16(dnsTypeSRV))
+	if err != nil {
+		t.Fatalf("answer: %v", err)
+	}
+	if g, e := len(addrs), 4; g != e {
+		t.Errorf("len(addrs) = %d; want %d", g, e)
+		t.Logf("addrs = %#v", addrs)
+	}
+}
+
+// Valid DNS SRV reply
+const dnsSRVReply = "0901818000010005000000000c5f786d70702d736572766572045f74637006676f6f67" +
+	"6c6503636f6d0000210001c00c002100010000012c00210014000014950c786d70702d" +
+	"73657276657234016c06676f6f676c6503636f6d00c00c002100010000012c00210014" +
+	"000014950c786d70702d73657276657232016c06676f6f676c6503636f6d00c00c0021" +
+	"00010000012c00210014000014950c786d70702d73657276657233016c06676f6f676c" +
+	"6503636f6d00c00c002100010000012c00200005000014950b786d70702d7365727665" +
+	"72016c06676f6f676c6503636f6d00c00c002100010000012c00210014000014950c78" +
+	"6d70702d73657276657231016c06676f6f676c6503636f6d00"
+
+// Corrupt DNS SRV reply, with its final RR having a bogus length
+// (perhaps it was truncated, or it's malicious) The mutation is the
+// capital "FF" below, instead of the proper "21".
+const dnsSRVCorruptReply = "0901818000010005000000000c5f786d70702d736572766572045f74637006676f6f67" +
+	"6c6503636f6d0000210001c00c002100010000012c00210014000014950c786d70702d" +
+	"73657276657234016c06676f6f676c6503636f6d00c00c002100010000012c00210014" +
+	"000014950c786d70702d73657276657232016c06676f6f676c6503636f6d00c00c0021" +
+	"00010000012c00210014000014950c786d70702d73657276657233016c06676f6f676c" +
+	"6503636f6d00c00c002100010000012c00200005000014950b786d70702d7365727665" +
+	"72016c06676f6f676c6503636f6d00c00c002100010000012c00FF0014000014950c78" +
+	"6d70702d73657276657231016c06676f6f676c6503636f6d00"